1. Industrial useful field
This invention relates to a mold releasing agent which is used by being sprayed onto inside surfaces of a molding die in a low pressure die casting work.
2. Prior art
A low pressure die casting method is being utilized widely in manufacturing various parts for automobile and electrical equipment because cast parts of high precision can be manufactured continuously and in large quantities by this method. And, in this low pressure die casting method, a mold releasing agent is used in order to prevent a molding die from direct contact with molten metal for avoiding seizure and for improving release of products from dies.
The low pressure die casting mold releasing agent is generally classified into two principal groups: a water soluble mold releasing agent and a water insoluble mold releasing agent. Among these agents, the water insoluble mold releasing agent includes problems from a standpoint of safety because of its large danger due to smoke and flammability so that the water soluble mold releasing agent is being used frequently. The water soluble mold releasing agent is generally composed of mold releasing base materials such as water, mineral oil etc., to which silicon oil, synthetic or natural wax, fats and oils, fatty acid ester etc. for use as surface active agent or extreme pressure providing agent, are annexed.
3. Problems to be solved by the Invention
Incidentally, with a progress of low pressure die casting technology in recent years, there has been an increasing demand for a mold releasing agent to obtain products of high quality with better workability. However, it has become impossible to satisfy this demand by using the water soluble mold releasing agent. Namely, the water soluble mold releasing agent has included problems that control of die temperature has been difficult due to its water solubility and there has been a high possibility of defects arising in product insides due to remaining water. Further, there has been a problem that liquid-waste treatment has become required for prevention of water pollution to induce increases in various expenses for plant and equipment investment. Therefore, a strong demand for a mold releasing agent of a new type has arisen.